Finishing process



Patented Sept. 29, 1942 UNITED STATE FINISHING PROCESS AlexanderJ.-Faust, Grosse Pointe, Mich.

No Drawing. Application March 14, 1938, Serial No. 195,851

11 Claims.

This invention relates to finishing or surfacing processes, and moreespecially to improved means for applying a metallic high lustrecoating, presenting the appearance of a plated surface,

yet applicable, without the use of electricity, by.

a relatively simple procedure involving the steps of painting andbufllng with particular substances, used in a particular sequence. Animportant aim of the invention is to produce such a metallic high-lustrecoating, of mirror-like quality, with the use of no other apparatus thana paint brush or paint sprayingequipment, and bufiing means such as asoft cloth or fur pad.

Previously known non-electric processes for producing such a metallicfinish have employed various powdered metals, blown or dusted onto asurface, such as wet varnish, enamel or lacquer, to provide a coating ofmetal powder cemented to the surface by the paint-like under coating.Even if buffing is resorted to after such an application of metal powderover a wet paintlike coating, it has not been possible, however, tosecure a brilliant lustre, truly resembling a continuous metallicsurface, and although the dull metallic finishes secured by suchpreviously known processes provide an attractive surface, suitable formany uses, they are in no sense a substitute for platings of nickel,chrome or the like, such as are commonly employed when a bright metallicfinish is required. The present process aims to provide a finishingsurface coating constituting a substitute for deposited metal plating,and presenting the true appearance of a continuous, polished ornaturally brilliant metallic surface, strongly resembling chromium, yetthe creation of which is no more difficult or expensive thanconventional painting or varnishing processes.

A further object is the provision of such a finishing process which isapplicable to non-conducting surfaces.

Other objects will become apparent during the course of the subsequentdescription.

In carrying out my improved process, the surface to be finished is firstgiven a preparatory or undercoating of paint, varnish, enamel orlacquer, which maybe applied by brushing, spraying or dipping, and isthereafter allowed to dry. Best results have been secured with enamelsand lacquers which dry bright without rubbing. I prefer colorlesslacquer, although this is not essential. It should have a brilliantgloss when dry, and is allowed to drybefore proceeding.

Whenever hereafter, throughout the specificaelectrotion and claims, thewords paint or paintlike are used, they are to be understood asincluding any initially liquid coating material of the general classabove indicated.

The next step is to spread over the undercoating a finely flaked metal,and to cause the flaked particles to leaf together or form a film Ihaving a highly polished surface, which appears to be continuous anduniform. This may be done in several relatively simple ways. In fact, inperfecting my process I had relatively little difficulty in securing amirror-like finish with the use of powdered or flaked metal, but greatdifficulty in developing a simple and practical method of preserving thehigh lustre against deterioration, since not "only the atmosphere, butmost finishes which might be placed thereover, 'destroy its mirror-likequality and seem to attack the metal.

My preferred method of securing the metallic coating is to apply byrubbing directly over the undercoating a substance of the characterdescribed in Patent No..2,002,891, issued May 28, 1935, to Harriet 1.Hall, as executrix of Everett J. Hall, or some such variation of thatproduct as is sold in the trade, and known as aluminum paste. Thiscontains varying quantities, usually something over half, flakedaluminum, small quantities (about 1% each) of stearic acid and aluminumstearate, and a vehicle in the nature of a petroleum oil or grease;

such as that known in the trade as Varnolene. The aluminum paste isrubbed over the surface and polished to high brilliance with a softcloth or other suitable bumng means, which causes the flakes to assume aflat position parallel to the surface, and apparently to flow togetherat their margins, imparting a continuous and highly polished appearance.All excess is rubbed off, and it will be found that the thin, highlypolished film adheres to the undercoating with great tenacity, for areason which I have not been able to determine accurately, although itmay be that the petroleum content of the aluminum paste slightly attacksthe surface of the undercoating, rendering it slightly adherent withoutactually destroying its smoothness.

An alternative method of forming the metallic coating is merely to rubthe surface of the undercoating with a suitable grease, such asVaseline, or other fluid substance capable of very mildly attacking theundercoating without destroying its smooth brilliance, rubbing 'suchfluid into the finish and rubbing off all excess, and

' then applying the metallic flaked powder, such as aluminum or bronze,by dusting it over the surface. Thereafter the powder must -be rubbedand polished in the same manner, by means of a sheeps wool or soft clothpolisher. It will be found that after a certain point in the rubbing,virtually none of the powder can be rubbed off, yet a very fine finishremains upon the enamel or other surface coating, as before.

When the metallic film has attained the desired brilliance, a protectingcoating of water-soluble gelatine is applied thereover, by spraying,brushing or in any desired manner. This may be very thin, but should dryhard and cover the entire finished surface in air-tight form. It isallowed to dry, and over the gelatine coating a more durable,water-resistant, transparent protecting film, such as colorless lacqueror varnish is applied, and this also may be put on either by brushing,spraying or dipping, If absolutely clear or water-white gelatine andlacquer are used, the finish remains extremely brilliant, and in factwhen aluminum is used it is difficult to distinguish it from chromeplate.

The application-of the indicated substances in the order named haspeculiar virtues. The gelatine adheres very tenaciously to the metallicfilm, yet is inert and does not attack either the metal or theundercoating, allowing the aluminum flakes to retain their positions andpolished condition. The lacquer or varnish on the other hand wouldattack the metallic film or allow' the flakes to turn to such positionsas to destroy the polished appearance, "if applied directly thereto, andwould quickly destroy the brilliance. Ordinary synthetic lacquers may beused for the top coating, and these adhere strongly to gelatine yet donot attack it, so that a lastingly bright finish is obtained.

The undercoating or surface need not be colorless, and in fact apleasing depth of tone is secured with a black under surface. It will beappreciated also that the undercoating or surface might be of anysuitable material to which the finely comminuted metal particles mightbe made to adhere, in the described or any suitable manner.

Without any gelatine or other coating over the metallic film, thebrilliance will last for a short while, and such finish may be usefulfor some purposes, where permanence is not required. If the gelatine isomitted and the lacquer is placed directly over the metallic film, agood protective finish is obtained, althoughthe bright lustre is notsecured.

If the gelatine is dissolved in hot water and a small percentage (about2%) of furfurol added. the gelatine is not only rendered resistant tobacteria, but may apparently be kept indefinitely in a sealed container,and remelted, when it is desired to use the same, by simply heatingjit.

What I claim is:

l. The surface coating process which comprises applying to a relativelyhard paint-like surface to be coated a softening agent which attacks thesurface only very slightly, thoroughly rubbing over and into suchsurface finely comminuted metal and buffing and orienting the same toprovide a high lustre surface parallel to said first mentioned surface.

2. The surface coating process which comprises applying to a relativelyhard paint-like surface to be coated a softening agent which attacks thesurface only very slightly, simultaneously rubbing over and into suchsurface finely comminuted metal and buffing and orientirg said orientedby such rubbing operation to lie substantially in one plane.

5. A process of applying an adherent metallic coating to a relativelyhard paint-like surface, which comprises spreading finely comminutedmetal over the surface and causing the comminuted particles to adhere tosaid surface, buffing the surface of the adhering particles to form ametallic film having a desired lustre, and covering said film with agelatine coating.

6. A process for applying an adherent metallic coating to a relativelyhard paint-like surface,

which comprises spreading finely comminuted metal over such surface andcausing the comminuted particles to adhere in a coating to said surface,removing the excess, non-adherent particles, coating the adheringparticles with a film of transparent material which is inert and unableto attack either saidsurface or the particles, and

coating said film with another film of transparent material which doesnot deleteriously affect the first mentioned film.

'7. The process of applying a lustrous metallic coating to a desiredsurface which comprises coating such surface with a smooth paint-likefilm and allowing such film to dry, applying to such film a fluid agentcapable of causing metal particles to adhere to the surface thereofwithout breaking down its smooth character, applying to such film, whilesaid agent or the effect thereof is still present, a finely comminutedmetal, rubbing the comminuted particles to form a sub stantiallycontinuous layer having a desired lustre and removing the excessthereof.

8. The surface coating process which comprises applying to a relativelyhard paint-like undercoating a mildly acting softening agent, rubbingsuch agent thoroughly into and from the surface to soften the same atthe top only to an extent which is imperceptible to the naked eye, andthen applying and rubbing onto the surface finely comminuted aluminum tocause the same to adhere thereto and to provide a buffed surfacecontinuous in appearance and substantially parallel another initiallyliquid layer of translucent protective gelatinous material, thepaint-like layer being insoluble in the liquid constituent of said lastmentioned protective material, and the metallic coating being sealedbetween said layers.

10. The process of forming a composite film having a.

gh metallic lustre, which comprises laying down an initiallyliquidpaint-like base layer; allowing the same to harde the hardenedlayer being insoluble in water, then spreading over said hardened layera plurality 'oiflne metallic particles, bufiing the particles to orient;and polish the same to provide a metallic coatin which appears to theeye as a smooth and substantially continuous surface parallel to theplane of said layer, causing said particles to cling to the surface onlyof said hardened layer, covering said metallic coating with a secondinitially liquid layer of adherent translucent protective gelatinousmaterial carried inowater as a vehicle, and

allowing said second layer to harden, whereby the vehicle of the secondmentioned layer, it it penetrates between. the metallic particles, isin-, capable of softening the base layer and so disturbing theorientation or the particles.

11. Theprocess of iorming acomposite fllm' having a high metalliclustre, which comprises laying down an initially liquid paint-like baselayer which is insoluble in water when dry, al-

lowing said material to harden, spreading over and causing to adhere tosaidbase layer a plurality of fine particles of metal, bufiing-saidparticles to orient and polish the same until they form ametallic-coating presenting a smooth and substantially continuoussurface, causing said particles to cling to thesurface only of saidhardened layer, applying to said metallic coating a layer formed ofanother initially liquid adherent transparent protective materialcarried in water as a vehicle and which is insoluble in an top layerformed of organic solvent, allowing said last mentioned protective layerto harden, and applying thereover a an initially liquid adherent andtransparent paint-like material carried in an organic vehicle which isincapable oi attacking the protective layer.

ALEXANDER J. FAUST.

